--- !Document
_tests: !List/Boolean
  - !Equal/String
    a: !SubString
      source: &645f6759-421e-4881-9137-346c0ea3ca37 "abcdef"
      first: 0
      count: 3
    b: "abc"
  - !Equal/String
    a: !SubString
      source: *645f6759-421e-4881-9137-346c0ea3ca37
      first: -3
      count: 3
    b: "def"
  - !Equal/String
    a: !SubString
      source: *645f6759-421e-4881-9137-346c0ea3ca37
      first: -1
      count: 3
    b: "f"
  - !Equal/String
    a: !SubString
      source: *645f6759-421e-4881-9137-346c0ea3ca37
      first: -9
      count: 3
    b: ""
  - !Equal/String
    a: !SubString
      source: *645f6759-421e-4881-9137-346c0ea3ca37
      first: 0
      count: -5
    b: ""
